Elastic Recovery and Performance of Denim Fabric Prepared by Cotton/Lycra Core Spun Yarns

ABSTRACT

Elastic performance coefficient (EPC) and recovery behavior of denim fabrics prepared with cotton/lycra core spun stretch yarns have been presented in this article. The denim fabrics are woven as broken twill weaves in an air-jet weaving machine by the insertion of core spun yarns (lycra filament in core, cotton fiber on sheath) as weft and using 100% cotton yarns as warp. The effect of linear density and stretch percentage of the core spun weft yarns on tensile and recovery behavior of denim fabric have been investigated by employing full factorial design of experiments. It has been observed that the tensile strength and EPC of fabric increase with decrease in linear density and stretch percentage of the core spun stretch yarn. The immediate elastic recovery and delayed elastic recovery increase with decrease in linear density and stretch percentage of the yarns.     

膨体弹力真丝重磅织物的设计与试制

介绍了以膨体弹力真丝为纬线设计试制的全真丝膨体弹力牛仔绸和文胸绸,通过性能测试及与同规格普通真丝绸的对比,表明了利用膨体弹力真丝新素材开发重磅机织物产品的良好前景     

Investigation on permeability and moisture management properties of different denim fabrics after repeated laundering

The physiological comfort determined by air permeability and moisture management properties of fabrics is influenced by various constructional parameters of the fabric which give woven fabric a porous structure. Evaporation of sweat during wear has the potential to cool the body besides restricting the additional weight of sweat being absorbed by the fabric. In this study, comfort characteristics of denim fabrics with different weft yarn of cotton, polyester and core spun Lycra have been discussed. Effect of enzyme washing and repeated laundering on air permeability, moisture management and drying rate has also been discussed. It was observed that air permeability and water vapour permeability of unwashed denim fabrics with cotton weft yarn are significantly higher than the fabric with polyester and Lycra cotton weft yarns. The wetting time is higher for cotton and Lycra cotton yarn fabrics. One-way transport index is highest for Lycra cotton weft fabrics and lowest for fabrics with polyester weft. Fabrics with polyester weft yarns show highest spreading rate, spreading radius and drying rate due to better wicking and hydrophobic nature of polyester fibres.     

Modeling the effect of elastane linear density,fabric thread density,and weave float on the stretch,recovery, and compression properties of bi-stretch woven fabrics for compression garments

The aim of this study was to investigate the effect of elastane linear density, thread density, and weave float on the stretch, recovery, and compression properties of bi-stretch woven fabrics for compression garments. Fabric samples were produced using elastane core-spun cotton yarns both in the warp and weft. The elastane linear density, fabric thread density, and weave float size were used as input variables while fabric contraction, subgarment pressure, fabric stretch, and recovery were taken as response variables. Two different elastane linear densities, i.e. 44 and 78 dtex, two different thread densities, and three different weave designs, i.e. 1/1 plain, 2/2 z-twill, and 3/3 z-twill were used. The results of fabric samples were analyzed in Minitab statistical software. The coefficients of determinations (R-sq values) of the regression equations showed good prediction ability of the developed statistical models. The findings of the study may be helpful in deciding appropriate manufacturing specifications of bi-stretch fabrics to attain specific stretch, recovery, and compression properties.     

Analysis of mechanical and dimensional properties of the denim fabrics produced with double-core and core-spun weft yarns with different weft densities

Elastic structures are preferred for improving the elasticity and recovery properties of denim fabrics. With the intention of improving comfort during body movements in denim jeans, 10–35% elasticity is required. In this study, the effect of the composition of double-core (dual-core) and core-spun weft yarns and weft density on the mechanical properties of denim fabrics was investigated. For this purpose, different core materials were used in the production of elastic yarns. The sheath material was cotton for all yarn types. Yarn samples were spun with the same yarn count and twist coefficient. 100% cotton Ne 8/1 Ring slub warp yarns were used as warp yarn while double-core and core-spun yarns were used as weft yarns in weaving. The weaving process was performed with three different weft density values (16, 22, and 28 weft /cm) and the other production parameters were kept constant. Twill 3/1 woven fabrics were treated according to standard denim finishing procedures. After domestic washing processes, mechanical properties of the samples were tested and statistically evaluated.     

Total porosity,theoretical analysis,and prediction of the air permeability of woven fabrics

Air permeability is one of the most important properties of textile materials that ensure their comfort. For many materials for technical applications (filters, sails, vacuum cleaners, parachutes, etc.), this is one of the main properties that determine their quality. The air permeability of woven textile fabrics depends on many parameters of fabric. Thus, the determination of air permeability of woven fabric is highly complex and difficult. In this study, we attempted to establish a theoretical model for the porosity and predicted the air permeability of woven fabrics. A theoretical model was created to predict the total porosity and the air permeability of a fabric structure depending on the geometrical parameters such as pore size, warp density, weft density, fabric thickness, number of yarn, diameter of yarn, and fiber density. For the purpose, a theoretical model of porous systems on D’Arcy’s law was used, and the validity of the model was confirmed by experimental results using 100% cotton and 97/3 cotton/lycra woven fabrics. Since the amount of air passing through both the pores between yarns and the interstices in the fibers constituting the yarn structure was calculated, theoretical values of air permeability were obtained very close to the experimental values.     

仿针织牛仔面料的开发及性能评价

为获得兼具针织和机织牛仔面料优点的新型牛仔面料,从纱线的选择、织造、后整理等方面探讨了仿针织牛仔面料的开发。对比测试了仿针织牛仔面料、针织牛仔面料、纯棉机织牛仔面料等5 种面料的拉伸断裂强力、撕破强力、色牢度等指标,并利用川端织物风格评价系统对牛仔面料的拉伸、剪切、弯曲、压缩、表面摩擦5 项指标进 行织物风格综合分析。结果表明,采用精梳纯棉纱作为经纱,涤纶长丝氨纶包芯纱作为纬纱,选择复合右斜纹组织,经特殊后整理工艺后生产的仿针织牛仔面料经向拉伸断裂强力高达685 N,撕破强力达59 N,粗犷挺括,柔软舒适,弹性和保型性俱佳,克服了针织牛仔面料和机织牛仔面料的风格缺陷。     

Studies on cotton-acrylic bulked yarns produced from different spinning technologies. Part II: fabric characteristics

The present work is concerned with the study of the characteristics of plain woven fabric produced with cotton-acrylic high-bulk yarns from different spinning technologies. The effects of different factors, namely spinning technologies (ring, rotor and DREF-II, i.e. Group A fabrics), position of shrinkable acrylic feed sliver in DREF-II friction spinning system (Group B fabrics) and proportion of shrinkable acrylic core fibre in core-sheath type DREF-III friction spun yarns (Group C fabrics) on various properties of cotton-acrylic blended bulked yarn fabrics have been reported. The influence of these three variables on the mechanical, handle and comfort properties of fabrics have been studied. The properties of fabrics made of bulked yarns from different spinning technologies are found to be different from the normal 100% cotton yarn fabrics in all respect. Even though the bulked yarns were used only in weft direction, the fabrics with modified yarn structures show appreciable improvement in thermal resistance, moisture vapour transmission, wicking and air permeability. The bending rigidity of the fabrics in weft direction also reduced with improvement in crease recovery in weft direction.     

Hand feeling style of spun silk/chitosan blended fabric北大核心CSCD

Spun silk and chitosan fiber were blended to fabricate spun silk/chitosan blended yarn with three blending ratios (90/10 and 80/20 and 70/30) by silk spinning technology. The silk/chitosan blended yarn and pure spun silk were used as warp and weft yarn to design and weave 16 fabrics. The 16 mechanical properties about fabric hand feeling were measured at low stress with KES-FB-AUTO fabric style instrument. Six basic style values (stiffness, flatness, suppleness, fullness, smoothness and scroopy) were calculated by Kawabata formula of women's fine dress fabrics. The results reveal that compared with a pure spun silk fabric, spun silk/chitosan blended fabrics have higher stiffness, flatness, smoothness and scroopy, but lower suppleness, and the fullness differs little. © 2017 China Silk Association. All rights reserved.     

PTT/绢丝混纺织物的风格及服用性能

为了将PTT纤维的形状记忆性与蚕丝优异的服用性能相互融合,以绢纺工艺将PTT纤维与绢丝混纺,制成混纺比为50:50的PTT/绢丝混纺纱,并以其为经纬纱设计织造了5种PTT/绢丝混纺面料,此外还以相同规格织造了3种纯绢纺纱对比试样。测定了这8种织物的手感、悬垂性及保形性(折皱回复性、拉伸回弹性)、透通性(透气、透湿性)和抗起毛起球性能,对比分析了PTT/绢丝混纺织物和纯绢丝织物的风格和服用性能。研究结果表明：PTT纤维对绢纺织物的风格与服用性能有良好的改善作用,与纯绢丝织物相比,PTT/绢丝混纺织物的折皱回复性、拉伸回弹性提高,柔软性和悬垂性好,滑糯性、透通性和抗起毛起球性能略差。     

Multi-response optimization of mechanical and comfort properties of bi-stretch woven fabrics using grey relational analysis in Taguchi method

The present paper envisages the multi-response optimization of certain factors like elastane linear density, fabric thread density and weave float on some mechanical, (i.e. stretch %, recovery %) and comfort (i.e. air permeability) properties of bi-stretch woven fabrics, under L₁₈ orthogonal array in Taguchi design. Fabric samples were produced using elastane core-spun cotton yarns both in the warp and weft. The elastane linear density, fabric thread density and weave float size were used as predictor variables, while fabric air permeability, stretch and recovery were taken as response variables. Two different elastane linear densities, i.e. 44 dtex and 78 dtex, 3 different thread densities and 3 different weave designs, i.e. 1/1 plain, 2/2 z-twill and 3/3 z-twill were used. The results have been analysed using grey relational analysis for the identification of an optimum level of process factors. Furthermore, using analysis of variance method, significant contributions of predictor variables were determined.     

A Study of the Mechanical Properties of Woven Silk Fabrics. Part III: A Study of the Extensibility of Continuous-filament Woven Silk Fabrics in the Small-load Region

Continuous–filament woven silk fabrics have a very low tensile modulus in the small-load region compared with woven fabrics of other fibres having a similar structure. In the silk fabrics, there may exist a small gap between the warp and weft threads at their crossover points because of the sericin-removing treatment that is applied after weaving. The tensile behaviour of a fabric with such a gap is considered to consist of two stages. In the first stage, the bent yarn alone is stretched in the initial state of tensile deformation without any mechanical interactions between the warp and weft threads. Since the bending rigidity of silk yarns is small and the gap is relatively large, the tensile modulus of silk fabrics becomes very low in the initial tensile region. After the contact of the warp and weft threads, the soft lateral-compressional property of the silk threads leads to extensibility of the silk fabric. This stage is called here the second stage, in which the tensile and the lateral-compressional deformation properties are mainly concerned with the tensile behaviour of the fabric in this region. Silk–fibroin fibre has a small fibre crimp, and this crimp also makes the silk yarn compressible. In this paper, the extensibility of silk fabrics is analysed, with a theoretical estimation of the extensibility, and an experiment to explain the reason for the high extensibility of silk fabrics is reported.     

用Dref 3摩擦纺多组分纬纱织造的织物的风格特征

研究分析了3种用Dref3摩擦纺多组分纬纱织造的平纹织物的风格特征。3种不同的纬纱是：芯皮均为粘纤;水溶性PVA作皮,粘胶无捻纱条作芯;PVA无捻纱条作芯,粘纤作皮。3种纱均在Dref3型摩擦纺机上按芯皮50／50比例纺成,经纱统一采用2合股纯棉纱线。将3种纱分别织成织物,然后用热水将PVA溶解去除。织物性能的测定结果：织物性能与组成织物的纱组分性能并不一致。无捻芯纱(溶掉PVA表皮)织物具有较高的拉伸强力、撕裂强力、折皱回复性和耐磨性;而空心纱(溶掉PVA作芯)织物具有丰满、蓬松的结构和良好的耐压缩性能。     

Study of wicking behavior of water on woven fabric using magnetic induction technique

An apparatus for measuring the wicking rise of water in fabrics has been developed and several types of fabrics were examined. The method is based on the electromagnetic field induction due to wicking penetration of water into capillary spaces of fabric samples. The measuring system is coupled with a personal computer, and the distance of water rise as a function of time is determined. Plain woven fabric samples with different weft yarn counts, density, and type of fiber in blend yarn were examined. The results obtained by wicking measurement were compared with water vapor permeability index data and the test method for wettability of textile fabrics on the same samples. The average wicking rise of water decreases with the increase of weft yarn density. The wicking of water along the cotton–polyester blend weft yarn is higher than 100% cotton weft yarn samples. The relation of water vapor permeability (WVP) index and the test method for wettability of the same fabric samples show the same behavior as the wicking rise. The equivalent geometric factor neglecting the Earth’s gravitational field is calculated by the average slope L ²/t from the experimental data of wicking of water into the samples. The radii of open channels in the woven fabric sample tends to decrease as a result of increasing weft yarn density.     

PTT织物与棉氨包芯纱织物的弹性比较

采用新型聚酯纤维———PTT织制了4种纬弹织物,选用2种市售棉氨包芯纱织物与其对比,实测了它们的应力-应变曲线和定伸长重复拉伸性能。通过实验,将PTT织物与棉氨包芯纱织物相比,PTT织物在高伸长下仍表现出低模量的特征;PTT织物弹性回复能力高,对人体有更好的收紧作用,可起到紧身健美的效果。     

Tensile and Frictional Properties of Wool-Cotton Union Khadi Fabrics

ABSTRACT

This paper describes the tensile and frictional behavior of wool-cotton union fabrics developed using different wool-cotton blended warp yarns, and mixed wool weft yarns spun on khadi spinning system. The tenacity and elongation at break of fabric increase with the blending of cotton with JK crossbred wool in the warp direction and high content of Australian merino wool in the weft direction, however, initial modulus decreases. The static and dynamic coefficient of friction positively correlates to the wool content in warp yarn and negatively correlates with linear density and the proportion of Australian merino wool in weft yarn.     

全真丝纬向弹力机织物的设计与分析

全真丝纬向弹力机织物的弹力主要利用强捻纬线的捻度释放来形成。只要将经纬紧度、经纬密度、织物组织、丝线排列方式及工艺合理配置，均可形成较为理想的纬向弹力织物。对试织的单层和双层多风格弹力绸的测试表明，设计织物的弹力均能达到中低弹水平。     

基于灰聚类方法的磁性纤维混纺织物湿舒适性评估

 为了研究磁性纤维织物中纱线原料和组织结构对织物湿舒适性的影响,扩展功能纤维的应用领域,采用磁性纤维/竹浆/棉混纺比为67/23/10的磁性纤维混纺纱与棉、竹/棉混纺纱进行交织,设计十种不同组织结构的织物,测试织物的透气性、透湿性和导湿性。利用灰色理论体系的灰聚类分析方法对数据结果进行评估,选取湿舒适性最优的织物原料与结构设计方案。结果表明：磁纤维混纺纱与竹纤维纱线分别为经、纬纱的平纹织物夏季湿舒适性最好;磁纤维混纺纱与竹纤维纱线分别为经、纬纱的接结双层织物冬季湿舒适性最好。     

棉/单芯涤纶长丝包芯纱织物的力学性能研究

文章对棉/单芯涤纶长丝包芯纱织物的力学性能指标进行了测试分析与比较,其断裂强度和撕裂强度均高于同规格纯棉环锭纱织物,经向的拉伸强度和撕裂强度比纬向的要大,而顶破性能则比纯棉环锭纱织物差。     

细针距纯棉紧密纺经编面料的开发

针织纯棉产品多数是纬编产品,经编品种极少。文章主要利用紧密纺纱线进行细针距纯棉经编面料的开发,取得了较好的效果,丰富了针织纯棉产品的种类。